Welcome in H.C.M.
I have gone through your query regarding feeling of lump in neck with bloated stomach, light headedness.
Considering all your symptoms it appears as you are having gastritis
(gastro esophageal reflex disease). You may take now-
1- Avoid spicy foods.
2- Avoid smoking
3- take adequate fluid orally.
4- Antacids with PPI.
Probably above will help you.